Stout: Fall back to ACPI ports on version read failure.

Sideband ports are not implemented in RO mode on Stout. It creates
problems when trying to read the EC version. Therefore, if version read
fails, assume we are in recovery and attempt to use the regular ACPI ports.

TEST=Manual. "mosys ec info" in recovery / RO mode.
BUG=chrome-os-partner:18004.
BRANCH=Stout.

Change-Id: Iebcf024b9b64823fafefa03a9293a8b1ee9f1188
Reviewed-on: https://gerrit.chromium.org/gerrit/44010
Commit-Queue: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org>
Tested-by: Shawn Nematbakhsh <shawnn@chromium.org>
3 files changed